Door locking system



Feb. 9, 1965 R. A. DEIBEL ETAL DOOR pocxmc sysmm 2 Sheets-Sheet 1 Original Filed June 2, 1958 INVENTOR. RJYMOND A-DE/BEL BY W/LL IIM C- R/E5TER and RAYMOND 9. P465- MMa A TTOR/VE Y5 Feb. 9, 1965 R. A. DEIBEL ETAL DOOR LOCKING SYSTEM 2 Sheets-Sheet 2 Original Filed June 2, 1958 m 5 T 5 mmmw v y VD. W i 2 n w 0 MMO W M MM Yu" J" MME BY CZUMM United States Patent 'Ofitice 3,168,932 Patented Feb. 9., 1965 This invention relates to an intrusion guard system for a vehicle and more particularly to both an improved valve and an improved lock actuating motor for such a system. The present invention is an improvement over the subject matter of Patent No. 3,084,757 issued April 9, 1963.

This application is a continuation of our copending application Serial No. 739,196, filed June 2, 1958, on a Door Locking System.

. In an intrusion guard system wherein a valve is adapted to cause selective communication of fluid pressure door lock actuating motors with a fluid pressure source to lock vehicle doors against intrusion, the successful operation of the system depends on unrestricted fluid movement to produce prompt, positive, substantialy simultaneous action of the fluid pressure lock actuating motors. Heretofore, valves which were used could not accomplish this function efliciently and economically because they utilized O-ring type of seals. On one hand, valve ports which could tages of the present invention will readily be. perceived hereafter.

In accordance with the above objects, thepresent invention relates to an improved valve constuction for a vehicle intrusion guard system. The valve utilizes a poppet valve arrangement which permits fluid pressure from a suitable source to communicate with a chamber within the valve through a relatively large aperture. A plurality of conduits leading tol the lock actuating fluid pressure motors communicate directly with the above-mentioned chamber so that when the relatively large aperture is opened by the poppet valve arrangement, all of the lock actuating economically be used with O-ring type of seals were so restricted in size that the desired unrestricted fluid flow through the valve was unobtainable. On the other hand, the O-ring types of seals which were sufliciently large to give eflicient operation did not have the desired life expectancy unless they were installed by the use of complex fabrication techniques at an undesirably high cost. Furthermore, the use of conventional poppet types of valves was not feasible because they would have resulted in a valve which would have been complex both in number of parts and in mode of operation, thereby increasing the valve cost and decreasing its life expectancy. It is with the overcoming of the foregoing deficiencies and shortcomings of the prior art that a part of this invention is concerned.

In addition to the foregoing, prior art systems utilized door lock actuating motors which were relatively complex and hence relatively costly. It is also with providing an improved fluid pressure motor that the present invention is concerned.

It is accordingly one object of the present invention to provide an improved control valve for a fluid pressure actuated intrusion guard system which is not only extremely efficient in that it will cause :a multiplicity of fluid pressure lock actuating motors to be actuated substantially simultaneously in a rapid, positive manner, but will also result in low valve fabrication costs and long valve life expectancy.

Another object of the present invention is to provide an improved valve for an intrusion guard system which not only automatically actuates door locking motors to a locking position upon the starting ofa vehicle, but also permits efficient remote controlled actuation of the door lock motors to either a locking or an unlocking position.

A further object of this invention is to provide an improved valve for an intrusion guard system ofa vehicle which is relatively small in size and simple in construction, thereby not only capable of being manufactured at a relatively low cost and capable of providing trouble-flee reliable operation, as mentioned above, but also reducing motors are actuated rapidly, positively, and substantially simultaneously. The poppet valve arrangement is constructed in such a manner that it requires a minimum of parts to perform its intended function thereby resulting in lower fabrication costs and greater reliability in operation. Furthermore, for the sake of over-all economy of the system, the improved valve incorporates an additional valve which permits selective remote-controlled actuation of the door lock motors to an open or closed position, this incorporation permitting both valves to be made from common part-s thereby further reducing its cost.

In addition to the foregoing advantages, another important advantage of the foregoing construction is that the substantially simultaneous rapid, positive action of the door locking motors causes the sound of the door locking operation to be amplified, thus alerting the vehicle operator when the doors are being locked without requiring the use of visual signaling devices which would distract the operators attention from the road. The valve aspect of the present invention will be more fully understood hereafter.

The present invention also relates to an improved door lock actuating motor. This motor, which is responsive to fluid pressure, possesses a plurality of pistons which are floatingly mounted within a housing. Depending on which portion of the housing is placed in communication with a fluid pressure source, one of said pistons will be actuated to move a lever in the required direction to lock or unlock a vehicle door. All of the aspects of the present invention will be more fully understood when the following portions of the specifications are read in conjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view of a portion of an automo tive vehicle incorporating the improved door locking system of the present invention;

FIG. 2 is a plan view of the topof the improved intrusion guard valve of the present invention;

FIG. 3 is a plan view of the bottom of the improved intrusion guard valve of the present invention;

FIG. 4 is a schematic representation of the entire intrusion guard system with certain elements thereof in crosssection and a portion of this figure being taken from line IV--IV of FIG. 2;

FIGS. 5 and 6 are detail views of a portion of the improved valve of the present invention showing the position elements of the valve assume under different conditions of operation; and

FIG. 7 is an enlarged detail view of a portion of the improved fluid pressure actuated door locking motor which is shown in cross section in a portion of FIG. 4.

In FIG. 1 a vehicle 10 is shown with an engine 11 having an intake manifold 12. Coupled to the intake manifold is a suitable vacuum tank 13 which is adapted to provide a constant sourceof vacuum when the vehicle is in operation, as is well known. While certain portions of the present system will henceforth be described as being vacuum operated, it will be appreciated that with suitable modifications they may be operated by the use of compressed air or hydraulic fluid.

The master control valve 14 of the intrusion guard system is coupled to fluid pressure tank 13 by-conduit 15. This valve is also coupled to the engine intake manifold by means of conduit 16. Suitable conduits (not numbered) coupleth'e. housing of valve 14 to door locking motors 17 which are positioned in the doors of the vehicle. Other conduits (not numbered) in FIG. 1 also couplevalve 14 to control levers 18 which are mounted inthe front vehicle doors, these levers permitting manual locking and unlocking of the doors from a remote position. As canbe seen from FIG. 1, suitable linkages (not numbered) couple fluid pressure motors 17 to door latching assemblies 19. It is believed that a detailed description of the fluid pressure circuits at this point is unnecessary since their operation will become apparent from the subsequent description of FIG. 4.

Reference is now made to FIG. 4 where the entire system is shown in greater detail. Insofar as pertinent here, the door latching assembly 19 consists of a bell crank lever 20 which is .pivotally mounted by pin 29' on housing 21. The conventional manual door locking and unlocking pin 22 having a shaft 23 is adapted to extend through the molding 24 of the vehicle door to actuate link 25 in a vertical direction. The movement of link 25 upwardly will cause lever 26 to pivot in a counter-clockwise direction about pin 27. After lever 26 has been pivoted, the movement of pin 28 to the right, as occurs when the door handle (not shown) on the outside of the vehicle is manipulated, will cause end 29 of lever 26 to abut flange 30 of bell crank lever 20 to cause it to pivot in a clockwise direction. This will cause lever 31 to pivot about pin 32 in a counter-clockwise direction against the bias of spring 33. When this occurs, tongue 34 of lever 31 will be moved away from ratchet wheel 35 which is coaxially mounted with rotary latch 37 on shaft 36 to thereby permit opening of the vehicle door. As shown in FIG. 4, the latching assembly 19 is in the locked position so that the manipulation of the door handle'on the outside of the door will cause pin 28 to move to the right and cause lever 26 which is actuated thereby to move to the right also. However, the end'29 of lever 26 will miss flange 30 of lever 20, thereby preventing the actuation of the above-described linkage which unlocks the door. A more detailed description of the above described latch will be found in the above-mentioned copending application. However, it is deemed that a more detailed description of this latch for the purposes of the present invention is unnecessary.

Upon initial starting of the engine 11, the increase in manifold vacuum within engine intake manifold 12 will be communicated through conduit 38 and check valve 39 to vacuum tank 13. The manifold vacuum will also communicate with master intrusion guard valve 14 through conduits 38 and 38'.

Master intrusion guard valve 14 consists of a housing 40 which has a portion thereof partitioned into a plurality of chambers 41 and 42 by flexible dia hragm 43. The existence of vacuum within conduit 38, which is coupled to valve inlet conduit 44, will cause opening of flapper valve 45 against the bias of spring 46, which causes it to normally remain seated on its seat (not numbered). Chamber 41 will thus be evacuated through fluted bore 48 in which shaft 47 is adapted to move. The vacuum which is produced within chamber 41 upon starting of the vehicle will cause flexible diaphragm 43 to move upwardly against the bias of spring 48' which tends to hold it in the position shown in the drawing. The upward movement of diaphragm 43 will carry shaft 47 with it because washer 49 abuts dished washer 50 which, in turn, engages the shoulder 52 of shaft 47.

As shaft 47 and collar 69, which is afiixed thereto, move upwardly, poppet valve 53 will be caused to move upwardly by spring 54 to engage seat 55 which is formed about aperture v56 in valve wall 57. This action is shown in detail in FIG. of the drawing. It will be noted that poppet valve 58 remains on its seat 59 (because of the existence of vacuum within conduit 63) until such time that head 60 of shaft 47 engages poppet valve 58. Continued upward movement of valve stem 47 will thereafter cause valve 58 to be moved upwardly off of its seat after valve 53 is seated on seat 55. Valves 53 and 58 will thereafter assume the position shown in FIG. 6, and chamber 61 will be in communication with vacuum tank 13 through conduits 64 and 63. The sequential ac'- tion of valves 53 and 58 in the above-described manner will prevent cross-porting between the vacuum tank 13 and chamber 42 (which is in communication with the atmosphere through strainer 62). It is to be noted that since poppet valves 53 and 58 are slidingly mounted on the reduced diameter portion of shaft 47, the prevention of the cross-porting is accomplished with a minimum of mechanical linkages thereby simplifying the construction of the valve notwithstanding the use of sequentially operating poppet valves. 7 V

A plurality of conduits 65 (FIGS. 4 and 3) are in direct communication with chamber 61. Each of these cori= duits may be coupled directly (or through T connections 66) to lock actuating motors 17. Because of the utiliza tion of the plurality of conduits 65 and because of the use of the poppet valve 53 and 58, unrestricted fluid movement produces prompt, positive, substantially simultaneous action of motors 17.

After poppet valve 58 is in an opened position, diaphragm 43 will seat gland valve 51 on its seat 67, thereby terminating the communication between manifold 12 and chamber 41. After the foregoing occurs spring 48 willcause flexible diaphragm 43 to return to its position shown in the drawing. A bleed screw 68 which is suitably mounted in housing 48 permits the return of air to chamber 41. The air which is trapped in chamber 42 bleeds through strainer 62.

The downward movement of diaphragm 43 causes a corresponding downward movement of dished washer 50, washer 49, washer 70 and shaft 47. At this point it will be noted that gland valve 51 is slidingly mounted on valve stem 47 so that it remains seated on its seat 67 while vacuum exists in manifold 12, the continuous seatmg of gland valve 51 preventing the actuation of diaphragm 43 which would cause the recycling of motors 17 due to fluctuations in the manifold pressure.

Collar 69 is fixedly mounted to valve stem 47, and as can be seen from FIG. 6, valve stem 47 will move downwardly a predetermined distance before collar 69 engages valve 53. However, the downward movement of valve stem 47 will'cause poppet valve 58 to move downwardly therewith due to the expansion of spring 69 which is interposed between valves 53 and 58 and due to the frictional engagement between stem 47 and valve 58. How ever, valve 53 remains in its uppermost position shown in FIGS. 5 and 6 (because of the force exerted by spring 54) until such time as collar 69 engages it. When valves 58 and 53 are in the position shown in FIG. 5, manifold chamber 61 of valve 14 is not in communication with either chamber 42 or with vacuum tank 13. Continued downward movement of valve stem 47 due to the expansion of spring 48 will cause collar 69 to engage valve 53- and move it against the bias of spring 54 to the position shown in FIG. 4. Because of the sequential action of valves 58 and 53, cross-porting through chamber 61 is prevented. More specifically, the valves 53 and 58 are so arranged on valve stem 47 that either valve seat 59 or valve seat 55 may be uncovered at any particular time, but both cannot be uncovered at the same time. When valve 53 has been moved to the position shown in FIG. 4 the conduits 65 may be vented to the atmosphere through manifold chamber 61, valve opening 56, chamber 42 and strainer 62.

The above described action of master'control valve 14 upon starting of the vehicle results in automatic actuation of door locking motors 17 to a position which will cause the locks 19 associated therewith tolock. the ve hicle door's against unauthorized intrusion. More specifically, the communication between vacuum tank 13 and conduits 65 in the above described manner will cause a vacuous condition to exist in conduit 71, which is in communication with housing 72 of motor 17 through port 73. Floatingly mounted within housing 72 are two pistons 74 and 75, each having a one-way flapper type valve therein. As can be seen from FIGS. 4 and 7, one-way valve 76 in piston 75 is pulled to an open position when vacuum is applied to conduit 71. However, one-way valve 77 in piston 74 remains closed under such a condition. Therefore, the space between pistons 75 and 74 will become evacuated and piston 74 will be caused to move downwardly against the bias of spring 78 to approach piston 75. In so doing, the underside of piston 74 engages nut 79 which is aifixed to motor shaft 80 and causes it to move downwardly to the position shown in FIG. 4. Shaft 80 is suitably afiixed as at 81 to link 25 of latching assembly 19. When link 25 is placed in its lower-most position, the latching assembly 19 will prevent the doors from being opened from the outside, as described in detail above. A flexible bellows 82 is suitably connected between shaft 80 and housing 72 of fluid motor 17 to prevent foreign particles from entering into the housing 72 during the movement of shaft 80.

After the locks have been actuated in the above-described manner on starting of the vehicle, the return of poppet valves 53 and 58 to the position shown in FIG. 4 permits motor 17 to be vented to the atmosphere through conduit 71, T 66, conduit 65, chamber 61, valve port 56, chamber 42 and strainer 62. This will permit spring 78 to cause motor pistons 75 and 74 to return to the position shown in FIG. 4. This action of pistons 74 and 75 permits manual door locking and unlocking pin 22 (FIG. 4) to be actuated to either lock or unlock the vehicle door independently of the operation of the intrusion guard system because the manual actuation of pin 22 permits nut 79 attached to shaft 88 to move without contacting pistons 74 and 75.

When the vehicle engine is shut oif, the loss of manifold vacuum permits lightspring 51 to return gland valve 51 to the position shown in FIG. 4, thereby preparing the intrusion guard system for an automatic locking operation on the subsequent starting of the vehicle.

The intrusion guard system of the present invention also permits manual remote controlled actuation of the door latching assembly 19 for causing the doors of the vehicle to be locked or unlocked, as in the instance of admitting a passenger to the vehicle while the engine is idling. To this end manual controls 18 (FIGS. 1 and 4) are suitably positioned within the vehicle, as in the front doors thereof. Alternately, a manual control such as 18 may be positioned on the vehicle dashboard, if desired. In the event it is desired to unlock a vehicle door from a remote position, it is only necessary to manipulate knob 83 in a clockwise direction about its pivot pin 84 to cause valve 85 to unseat. When this occurs vacuum will be caused to communicate between tank 13 and master valve chamber .89 through conduit 86, chamber 87 of the con trol valve 18, and conduit 88. This will cause diaphragm 44', which is made out of the same piece of flexible material as diaphragm 43, to move upwardly against the bias of spring 98. This movement will be accompanied by corresponding movement of valve stem 91 and the movement of poppet valve 92 from its seat 93 to its seat 94. After this action has been completed, vacuum tank 13 will be in communication with conduit 95 and housing 72 of fluid pressure motors 17 through conduits 96 (FIGS. 4 and 3) and T connection 97. This will cause oneway valve 77 to open in a manner analogous to that described above relative to valve 7 6. Since one-way valve 76 of piston 75 will remain closed, the chamber between these pistons will be evacuated and piston 75 will be 6 upward movement of shaft which, in turn, causes link 25 of latching assembly 19 to be moved. to a position where it permits the vehicle doors to be opened by the manipulation of the outside door handles.

When knob 83 of manual control switch 18 is released, valve will return to the position. shown in FIG. 4. Diaphragm 44 of valve 14 will also return to the position shown in the drawing because of the expansion of spring and the admission of air into chamber 89 through venting port 97. A strainer 98 (FIGS. 2 and 4) also facilitates the movement of diaphragm 44' because it permits air to enter and leave chamber 98' defined by this diaphragm and the valve housing.

After the doors have been unlocked in the manner described above by the use of control valve 18, they may be manually relocked by manipulating knob 83 of this valve in a counter-clockwise direction to unseat valve 99'. When this occurs the vacuum tank 13 is placed in communication with chamber 41 of valve 14 through conduit 86, valve chamber 99 and conduit 180. This will cause chamber 41 to be evacuated to cause diaphragm 43 to move upwardly and thereby actuate valves 53 and 58 in the above described manner to actuate fluid pressure motors 17 to lock the door locks.

A suitable vent (not shown) is provided either in piston 74 or piston 75 of fluid pressure motor 17 to prevent these pistons from being held together after the fluid pressure motor 17 no longer communicates with the source of vacuum.

It is to be noted that the use of poppet valves 53 and 58 and the plurality of conduits 65 in the intrusion guard master control valve permit unrestricted fluid movement to produce prompt, positive, substantially simultaneous action of the fluid pressure lock actuating motors.

While we have described the preferred embodiment of our invention, we desire it to be understood that it is not limited thereto, but may be otherwise embodied Within the scope of the following claims.

We claim:

1. A valve for a vehicle door locking system comprising a housing, a diaphragm in said housing, means for biasing said diaphragm in a predetermined direction, first conduit means adapted to couple said housing to a fluid pressure source in said vehicle to cause said diaphragm to move against the force of said biasing means in response to the operation of said vehicle, an atmospheric vent in said housing, a common manifold chamber in said housing, second conduit means adapted to extend between said housing and a source of fluid pressure, a plurality of third conduit means adapted to extend between said manifold chamber and fluid pressure door locking motors, and poppet valve means in said housing adapted to be actuated by said diaphragm for selectively causing door locking motors to communicate with either said source of fluid pressure through said second and third conduit means and said common manifold chamber or causing said motors to communicate with said atmospheric vent through said manifold chamber and said third conduit means, said poppet valve means comprising a shaft adapted to be actuated by said diaphragm and first and second poppet valves mounted on said shaft for movement relative thereto, a first port in said common manifold chamber adapted to coact with said first poppet valve for selectively permitting communication between said atmospheric vent and said common manifold chamber, a second port in said common manifold chamber adapted to coact with said second poppet valve for selectively permitting communication between said source of fluid pressure and said common chamber, and means for causing said first and second poppet valves to operate sequentially in response to movement of said shaft to prevent cross-porting between said first andsecond ports.

2. In a vehicle having an engine for operating said vehicle; a valve for a vehicle door locking system comprising a housing, a diaphragm in said housing, means for biasing said diaphragm in a predetermined direction, first conduit means adapted to couple said housing to a fluid pressure source in said'vehicle to actuate said diaphragm to move against the force of said biasing means in response to initial starting of the vehicle engine of said vehicle, an atmospheric vent in said housing, a common manifold chamber in said housing, second conduit means adapted to extend between said housing and a source of fluid pressure, a plurality of third conduit means adapted to extend between said manifold chamber and fluid pressure door locking motors, and poppet valve means in said housing adapted to be actuated by said diaphragm for selectively causing door locking motors to communicate with either said source of fluid pressure through said second and third conduit means and said common manifold chamber or causing said motors to communicate with said atmospheric vent through said manifold chamber and said third conduit means and valve means actuated by said diaphragm for interrupting said coupling between said first conduit means and said housing and means for preventing repeated actuation of said diaphragm subsequent to initial starting and prior to subsequent stopping of said vehicle.

3. In a motor vehicle including an engine having an intake manifold which provides a source of vacuum when the engine is operating; a valve for a vehicle door locking system comprising a valve housing including a first chamber portion and a manifold chamber, a diaphragm dividing said first chamber portion into a first chamber and a second chamber, means for connecting said intake manifold to said first chamber to supply vacuum for actuating said diaphragm in response to initial increase of manifold vacuum upon starting of the vehicle engine, an atmospheric vent communicating with said second chamber, first conduit means in communication with said housing for permitting communication between said housing and a source of fluid pressure, second conduit means in communication with said manifold chamber for permitting communication between said manifold chamber and a plurality of fluid pressure door lock actuating motors, poppet valve means operatively connected to said diaphragm for movement therewith for controlling communication between said first conduit and said manifold chamber and between said second chamber and said manifold chamber to permit communication between said manifold chamber and said second chamber while interrupting communication between said manifold chamber and said first conduit when in one position and to permit communication upon actuation of said diaphragm in response to initial increase of manifold vacuum upon starting of the vehicle engine between said manifold chamber and said first conduit while interrupting communication between said manifold chamber and said second chamber in a second position whereby fluid flow between said fluid pressure source and said fluid pressure motors is interrupted and said fluid pressure motors are vented when said poppet valve is in said one position and whereby substantially unrestricted fluid flow between said fluid pressure source and said fluid pressure motors is permitted when said poppetvalve means is in said second position.

4. A valve as set forth in claim 3 including metered atmospheric bleed means in said first chamber.

5. A valve for avehicle door locking system comprising a valve housing including a first chamber portion and a manifold chamber, a diaphragm dividing said first chamber portion into a first chamber and a second chamber, fluid pressure means for actuating said diaphragm, an atmospheric vent communicating with said second chamber, first conduit means in communication with said housing for permitting communication between said housing and a source of fluid pressure, second conduit means in communication with said manifold chamber for permitting communication between said manifold chamber and a plurality of fluid pressure door lock actuating motors, poppet valve means operatively connected to said diaphragm for movement therewith for controlling com munication between said first conduit and said manifold chamber and between said second chamber and said manifold chamber to permit communication between said manifold chamber and said second chamber while interrupting communication between said manifold chamber and said first conduit when in oneposition and to permit communication between said manifold chamber and said first conduit while interrupting communication between said manifold chamber and said second chamber in a second position whereby fluid fiow between said fluid pressure source and said fluid pressure motors is interrupted and said fluid pressure motors are vented when said poppet valve is in said one position and whereby substantially unrestricted fluid flow between said fluid pressure source and said fluid pressure motors is permitted when said poppet valve means is in said second position and having means including a valve actuated by said diaphragm for automatically interrupting communication between said fluid pressure means and said first chamber when said poppet valve means is disposed in said second position.

References Cited by the Examiner UNITED STATES PATENTS A. HARRY LEVY, Primary Examiner. 

1. A VALVE FOR A VEHICLE DOOR LOCKING SYSTEM COMPRISING A HOUSING, A DIAPHRAGM IN SAID HOUSING, MEANS FOR BIASING SAID DIAPHRAGM IN A PREDETERMINED DIRECTION, FIRST CONDUIT MEANS ADAPTED TO COUPLED SAID HOUSING TO A FLUID PRESSURE SOURCE IN SAID VEHICLE TO CAUSE SAID DIAPHRAGM TO MOVE AGAINST THE FORCE OF SAID BIASING MEANS IN RESPONSE TO THE OPERATION OF SAID VEHICLE, AN ATMOSPHERIC VENT IN SAID HOUSING, A COMMON MANIFOLD CHAMBER IN SAID HOUSING, SECOND CONDUIT MEANS ADAPTED TO EXTEND BETWEEN SAID HOUSING AND A SOURCE OF FLUID PRESSURE, A PLURALITY OF THRID CONDUIT MEANS ADAPTED TO EXTEND BETWEEN SAID MANIFOLD CHAMBER AND FLUID PRESSURE DOOR LOCKING MOTORS, AND POPPET VALVE MEANS IN SAID HOUSING ADAPTED TO BE ACTUATED BY SAID DIAPHRAGM FOR SELECTIVELY CAUSING DOOR LOCKING MOTORS TO COMMUNICATE WITH EITHER OF SOURCE OF FLUID PRESSURE THROUGH SAID SECOND AND THIRD CONDUIT MEANS AND SAID COMMON MANIFOLD CHAMBER OR CAUSING SAID MOTOR TO COMMUNICATE WITH SAID ATMOSPHEREIC VENT THROUGH SAID MANIFOLD CHAMBER AND SAID THIRD CONDUIT MEANS, SAID POPPET VALVE MEANS COMPRISING A SHAFT ADAPTED TO BE ACTUATED BY SAID DIAPHRAGM AND FIRST AND SECOND POPPET VALVES MOUNTED ON SAID SHAFT FOR MOVEMENT RELATIVE THRETO, A FIRST PORT IN SAID COMMON MANIFOLD CHAMBER ADAPTED TO COACT WITH SAID FIRST POPPET VALVE FOR SELECTIVELY PERMITTING COMMUNICATION BETWEEN SAID ATMOSPHERIC VENT AND SAID COMMON MANIFOLD CHAMBER, A SECOND PORT IN SAID COMMON MANIFOLD CHAMBER ADAPTED TO COACT WITH SAID SECOND POPPET VALVE FOR SELECTIVELY PERMITTING COMMUNICATION BETWEEN SAID SOURCE OF FLUID PRESSURE AND SAID COMMON CHAMBER, AND MEANS FOR CAUSING SAID FIRST AND SECOND POPPET VALVES TO OPERATE SEQUENTIALLY IN RESPONSE TO MOVEMENT OF SAID SHAFT TO PERVENT CROSS-PORTIONG BETWEEN SAID FIRST AND SECOND PORTS. 